In general, colored plastics or polymer materials are desirable for use in a variety of applications, such as plastic consumer products and polymer composite building materials. Such colored plastics and polymer materials provide improved appearance and aesthetic character to the objects into which they are formed. Typically, pigments or dyes are added to polymer materials to produce the colored polymer materials.
However, traditional colored polymer materials can fade, lose color, or undergo aesthetically displeasing color changes. Traditional dyes may leach from the polymer material or may lose color or bleach through thermal degradation or degradation caused by exposure to radiation, such as ultraviolet electromagnetic radiation. Leaching is a particular problem for dyes blended in halogenated polyolefins. As such, polymer materials including such dyes may have poor color fastness.
In addition, dispersion of traditional pigments with polymer materials is difficult. Poor dispersion leads to swirling and color variability with the colored polymer material. Further, poor dispersion of the pigment within the plastic article may lead to undesirable mechanical properties. As such, compatibilizers are typically used to disperse pigment within a polymer material. Such compatibilizers include a variety of organic compounds that aid in dispersing the pigment. In addition, pigments are dispersed using high shear mechanical processes. However, compatibilizers typically are expensive and may also influence mechanical properties of the colored polymer material.
Accordingly, there is a continued need within the industry to provide pigments and plastics having improved fastness, stability and resistance to bleaching and color leaching.